1. Field of the Invention
This invention relates to swim fins and more particularly swim fins of an advanced design that will allow canceling vortices and better propulsion.
2. Description of the Related Art
With the advancement of scuba diving and snorkeling, swim fins have likewise developed in order to propel the diver through the water. As with the swimming fins of fish, swim fins for human beings have certain dynamic characteristics that provide for different types of propulsion through the water.
The analogy with fish and aquatic mammal fins is particularly apropos, as such fish fins serve to propel fish ranging in size from the smallest minnow to the largest whale. Additionally, if the rules of natural selection are assumed, the development of fish fins for particular activities serves as an indication of advantageous architecture to be adopted in diving fins.
Different species of fish and fish living in different environments have adapted over the thousands of generations to both interspecies and intraspecie competition so that those fish with the most efficient or better fin configuration, geometry, or architecture have a better advantage with respect to other members of their species not so endowed. Over time, advantageous characteristic features are adopted while detrimental or disadvantageous features are eliminated, as individual members of the species compete against one another. As fish are especially adapted for swimming and living in aquatic environments, the arrangement, structure, and architecture of the fins, particularly the fins used for propulsion, are a significant element to the fish""s anatomy and its ability to compete and survive with respect to other members of the species.
Ichthyologists characterize fish in a number of ways according to their body type and habitat. Some fish live generally at the surface of the water, others at the bottom, some around coral reefs, and some are deep water, pelagic, fish that are generally in a constant state of motion and generally always swimming. The rear propulsion, or tail, fin of the fish is known as the caudal fin, and may take a number of forms. These include a rounded caudal fin, a truncate caudal fin, a forked caudal fin, and a lunate caudal fin.
Fish with truncate or rounded caudal fins are usually strong swimmers, but are generally slow. Apparently, such truncate or rounded caudal fins provide strength but not speed to the propulsive force of the fish while swimming due to the greater centralized surface area of such caudal fins. Fish with forked caudal fins are generally those that continuously swim. An example of such fish are sharks, which, having no swim bladder, must continually swim in order to maintain their buoyancy. In some sharks, the top fork of the forked caudal fin is elongated to increase the upward force on the fish to hold its vertical position in the water as it swims. Fish with lunate caudal fins tend to be the fastest fish, with such fish being able to maintain relatively high speeds for long durations. Such fish include tuna, mackerel, and jacks, which have a fusiform shape and are generally the fastest fish in the ocean.
Beyond the specific construction of fish fins, fish also have the ability to bring their musculature to bear upon the instant geometry of their fins. Thus, it is an advantage not yet realized in the art to provide a swim fin that allows the diver to adjust the pitch and tension of the diver""s swim fin blade, regardless of the specific geometry of the swim fin blade. Furthermore, the art of swim fins would be enhanced and expanded by the ready substitution of one adjustable swim fin blade by another, both swim fin blades being adjustable in pitch and tension.
Most bladed swim fins, particularly those often used in conjunction with scuba and skin diving, are bladed fins having a pair of rails extending outwardly from a foot pocket. Webbing is present in the form of elastic or plastic webbing that forms a blade by which the diver propels him- or herself. Such swim fins often resemble the rounded or truncate caudal fins present on fish. Consequently, such swim fins provide strength, but generally not speed. As a result, skin and scuba divers swimming around reefs and trying to cover longer distances in calm waters must generally work harder in order to propel themselves faster. Additionally, such bladed swim fins are not adjustable, the lateral rails and the blade webbing not providing any adjustment with respect to the foot pocket or adjustment with respect to the pitch and/or tension of the swim fin blade.
By taking advantage of the development in fish fins nature has achieved, a swimmer or diver could better propel him- or herself by adopting a swim fin blade configuration that allows for greater speed and easier propulsion. Additionally, by improving upon present-day swim fins, greater adjustability and tailoring of fin blade performance would allow divers to conform fin blade operation to the diver""s preferences.
The present invention provides swim fins with adjustable wing members having a greater degree of forkedness or lunateness such as that which is often found with the caudal fins of faster-swimming fish. The individual wing members are selectably adjustable by means of a clock or timing washer so that the attitude or disposition of the individual wing members may be selectively positioned with respect to the foot pocket.
In an alternative embodiment, the webbing between the laterally extended rails of the swim fin blade may be discontinuous down its center, thereby allowing water flow in between the two halves of the swim fin blade. In a preferred embodiment, such webbing is continuous and adjustable according to the adjustment of extended rails.
Opposite and opposing vortices may be generated as by the forked or lunate caudal fins of faster swimming fish. Such discontinuity allows the passage of water through the blade of the fin and generally forces the fin to transmit propulsive power rearward, not dispersing it laterally. The lateral dispersion of the swim kick energy generally is not desired by the swimmer, as it does nothing to propel him or her forward. Attitude in the swimmer is generally controlled by shifting the direction of the propulsive power of the swim fins. By concentrating such power rearwardly, the swimmer gets more distance per kick and can travel faster and better through the water.
Alternatively, a cross-connected embodiment of the individual wing member embodiment may be achieved to deliver particular operating performance in the adjustable flexion of the fin.
In the present invention, the blade member(s) are rotatably attached to the foot pocket by clock washers or otherwise. Such rotatable adjustment provides for the adjustment of the pitch, tension, stiffness and/or orientation of the blade/hydrofoil portion of the fin and the effect of the blade/hydrofoil upon the flow of water about it.
It is an object of the present invention to provide a swim fin having articulated wing members.
It is another object of the present invention to provide a swim fin that provides greater propulsive force.
It is yet another object of the present invention to provide a swim fin that provides better rearward thrust.
It is yet another object of the present invention to provide a swim fin that is adjustable.
It is another object of the present invention to provide a swim fin with fin blades that are adjustable in tension, pitch, geometry, or a combination of each.
It is yet another object of the present invention to provide a swim fin with an interchangeable swim fin blade that is adjustable in its pitch, its tension, and its geometry.
It is yet another object of the present invention to provide a swim fin that generates vortices advantageously.
It is yet another object of the present invention to provide a swim fin that concentrates the swim kick energy into propulsive force.
It is yet another object of the present invention to provide a swim fin that uses available materials and is readily manufacturable.
It is yet another object of the present invention to provide a swim fin with blade adjustment features so as to provide a more versatile and useful swim fin.
These and other objects of and advantages of the present invention will be apparent from a review of the following specification and accompanying drawings.